configure.ac: Add autoconfery for theoradec.

Original commit message from CVS:
* configure.ac:
Add autoconfery for theoradec.
* ext/Makefile.am:
Add theora directory.
* ext/theora/Makefile.am:
* ext/theora/theoradec.c: (gst_theoradec_base_init),
(gst_theoradec_class_init), (gst_theoradec_init),
(gst_theoradec_reset), (inc_granulepos), (theora_get_query_types),
(gst_theoradec_granule_clocktime), (theora_dec_src_convert),
(theora_dec_sink_convert), (theora_dec_src_query),
(theora_dec_sink_query), (theora_dec_src_event),
(theora_dec_sink_event), (theora_handle_comment_packet),
(theora_handle_type_packet), (theora_handle_header_packet),
(theora_dec_push), (theora_handle_data_packet), (theora_dec_chain),
(theora_dec_change_state), (plugin_init):
* ext/theora/theoradec.h:
Add theora plugin for theora-exp decoder. Very heavily based on the
existing theora decoder plugin.

3 files changed, 1212 insertions, 0 deletions

diff --git a/ext/theora/Makefile.am b/ext/theora/Makefile.am
new file mode 100644
index 00000000..b361d96f
--- /dev/null
+++ b/ext/theora/Makefile.am
@@ -0,0 +1,12 @@
+plugin_LTLIBRARIES = libgsttheoraexp.la
+
+noinst_HEADERS = theoradec.h
+
+libgsttheoraexp_la_SOURCES = theoradec.c
+libgsttheoraexp_la_CFLAGS = $(GST_CFLAGS) $(THEORADEC_CFLAGS) $(GST_PLUGINS_BASE_CFLAGS)
+libgsttheoraexp_la_LDFLAGS = $(GST_PLUGIN_LDFLAGS)
+libgsttheoraexp_la_LIBADD = \
+	-lgsttag-@GST_MAJORMINOR@ \
+	$(GST_LIBS) \
+	$(THEORADEC_LIBS) \
+	$(GST_PLUGINS_BASE_LIBS)
diff --git a/ext/theora/theoradec.c b/ext/theora/theoradec.c
new file mode 100644
index 00000000..b0bc1313
--- /dev/null
+++ b/ext/theora/theoradec.c
@@ -0,0 +1,1104 @@
+/* GStreamer
+ * Copyright (C) 2004 Benjamin Otte <in7y118@public.uni-hamburg.de>
+ *               2006 Michael Smith <msmith@fluendo.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+/**
+ * SECTION:element-theoradec
+ * @see_also: theoraenc, oggdemux
+ *
+ * <refsect2>
+ * <para>
+ * This element decodes theora streams into raw video using the theora-exp
+ * decoder
+ * <ulink url="http://www.theora.org/">Theora</ulink> is a royalty-free
+ * video codec maintained by the <ulink url="http://www.xiph.org/">Xiph.org
+ * Foundation</ulink>, based on the VP3 codec.
+ * </para>
+ * <para>
+ * </para>
+ * <title>Example pipeline</title>
+ * <programlisting>
+ * gst-launch -v filesrc location=videotestsrc.ogg ! oggdemux ! theoraexpdec ! xvimagesink
+ * </programlisting>
+ * This example pipeline will demux an ogg stream and decode the theora video,
+ * displaying it on screen.
+ * </refsect2>
+ */
+
+#ifdef HAVE_CONFIG_H
+#  include "config.h"
+#endif
+
+#include "theoradec.h"
+#include <gst/tag/tag.h>
+
+GST_DEBUG_CATEGORY (theoradecexp_debug);
+#define GST_CAT_DEFAULT theoradecexp_debug
+
+static GstElementDetails theora_dec_details =
+GST_ELEMENT_DETAILS ("TheoraExpDec",
+    "Codec/Decoder/Video",
+    "decode raw theora streams to raw YUV video",
+    "Benjamin Otte <in7y118@public.uni-hamburg.de>, "
+    "Wim Taymans <wim@fluendo.com>, " "Michael Smith <msmith@fluendo,com>");
+
+/* TODO: Support for other pixel formats (4:4:4 and 4:2:2) as supported by the
+ * theoraexp codebase
+ */
+static GstStaticPadTemplate theora_dec_src_factory =
+GST_STATIC_PAD_TEMPLATE ("src",
+    GST_PAD_SRC,
+    GST_PAD_ALWAYS,
+    GST_STATIC_CAPS ("video/x-raw-yuv, "
+        "format = (fourcc) I420, "
+        "framerate = (fraction) [0/1, MAX], "
+        "width = (int) [ 1, MAX ], " "height = (int) [ 1, MAX ]")
+    );
+
+static GstStaticPadTemplate theora_dec_sink_factory =
+GST_STATIC_PAD_TEMPLATE ("sink",
+    GST_PAD_SINK,
+    GST_PAD_ALWAYS,
+    GST_STATIC_CAPS ("video/x-theora")
+    );
+
+GST_BOILERPLATE (GstTheoraExpDec, gst_theoradec, GstElement, GST_TYPE_ELEMENT);
+
+static gboolean theora_dec_sink_event (GstPad * pad, GstEvent * event);
+static GstFlowReturn theora_dec_chain (GstPad * pad, GstBuffer * buffer);
+static GstStateChangeReturn theora_dec_change_state (GstElement * element,
+    GstStateChange transition);
+static gboolean theora_dec_src_event (GstPad * pad, GstEvent * event);
+static gboolean theora_dec_src_query (GstPad * pad, GstQuery * query);
+static gboolean theora_dec_src_convert (GstPad * pad,
+    GstFormat src_format, gint64 src_value,
+    GstFormat * dest_format, gint64 * dest_value);
+static gboolean theora_dec_sink_convert (GstPad * pad,
+    GstFormat src_format, gint64 src_value,
+    GstFormat * dest_format, gint64 * dest_value);
+static gboolean theora_dec_sink_query (GstPad * pad, GstQuery * query);
+
+static const GstQueryType *theora_get_query_types (GstPad * pad);
+
+static void
+gst_theoradec_base_init (gpointer g_class)
+{
+  GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
+
+  gst_element_class_add_pad_template (element_class,
+      gst_static_pad_template_get (&theora_dec_src_factory));
+  gst_element_class_add_pad_template (element_class,
+      gst_static_pad_template_get (&theora_dec_sink_factory));
+  gst_element_class_set_details (element_class, &theora_dec_details);
+}
+
+static void
+gst_theoradec_class_init (GstTheoraExpDecClass * klass)
+{
+  GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);
+
+  gstelement_class->change_state = theora_dec_change_state;
+
+  GST_DEBUG_CATEGORY_INIT (theoradecexp_debug, "theoradecexp", 0,
+      "Theora decoder");
+}
+
+static void
+gst_theoradec_init (GstTheoraExpDec * dec, GstTheoraExpDecClass * g_class)
+{
+  dec->sinkpad =
+      gst_pad_new_from_static_template (&theora_dec_sink_factory, "sink");
+  gst_pad_set_query_function (dec->sinkpad, theora_dec_sink_query);
+  gst_pad_set_event_function (dec->sinkpad, theora_dec_sink_event);
+  gst_pad_set_chain_function (dec->sinkpad, theora_dec_chain);
+  gst_element_add_pad (GST_ELEMENT (dec), dec->sinkpad);
+
+  dec->srcpad =
+      gst_pad_new_from_static_template (&theora_dec_src_factory, "src");
+  gst_pad_set_event_function (dec->srcpad, theora_dec_src_event);
+  gst_pad_set_query_type_function (dec->srcpad, theora_get_query_types);
+  gst_pad_set_query_function (dec->srcpad, theora_dec_src_query);
+  gst_pad_use_fixed_caps (dec->srcpad);
+
+  gst_element_add_pad (GST_ELEMENT (dec), dec->srcpad);
+
+  dec->queued = NULL;
+}
+
+static void
+gst_theoradec_reset (GstTheoraExpDec * dec)
+{
+  dec->need_keyframe = TRUE;
+  dec->last_timestamp = -1;
+  dec->granulepos = -1;
+  gst_segment_init (&dec->segment, GST_FORMAT_TIME);
+
+  GST_OBJECT_LOCK (dec);
+  dec->proportion = 1.0;
+  dec->earliest_time = -1;
+  GST_OBJECT_UNLOCK (dec);
+}
+
+static gint64
+inc_granulepos (GstTheoraExpDec * dec, gint64 granulepos)
+{
+  gint framecount;
+
+  if (granulepos == -1)
+    return -1;
+
+  framecount = th_granule_frame (dec->dec, granulepos);
+
+  return (framecount + 1) << dec->info.keyframe_granule_shift;
+}
+
+static const GstQueryType *
+theora_get_query_types (GstPad * pad)
+{
+  static const GstQueryType theora_src_query_types[] = {
+    GST_QUERY_POSITION,
+    0
+  };
+
+  return theora_src_query_types;
+}
+
+static GstClockTime
+gst_theoradec_granule_clocktime (GstTheoraExpDec * dec, ogg_int64_t granulepos)
+{
+  /* Avoid using theora_granule_time, which returns a double (in seconds); not
+   * what we want
+   */
+  if (granulepos >= 0) {
+    guint64 framecount = th_granule_frame (dec->dec, granulepos);
+
+    return gst_util_uint64_scale_int (framecount * GST_SECOND,
+        dec->info.fps_denominator, dec->info.fps_numerator);
+  }
+  return -1;
+}
+
+static gboolean
+theora_dec_src_convert (GstPad * pad,
+    GstFormat src_format, gint64 src_value,
+    GstFormat * dest_format, gint64 * dest_value)
+{
+  gboolean res = TRUE;
+  GstTheoraExpDec *dec;
+  guint64 scale = 1;
+
+  if (src_format == *dest_format) {
+    *dest_value = src_value;
+    return TRUE;
+  }
+
+  dec = GST_THEORA_DEC (gst_pad_get_parent (pad));
+
+  /* we need the info part before we can done something */
+  if (!dec->have_header)
+    goto no_header;
+
+  switch (src_format) {
+    case GST_FORMAT_BYTES:
+      switch (*dest_format) {
+        case GST_FORMAT_DEFAULT:
+          *dest_value = gst_util_uint64_scale_int (src_value, 2,
+              dec->info.pic_height * dec->info.pic_width * 3);
+          break;
+        case GST_FORMAT_TIME:
+          /* seems like a rather silly conversion, implement me if you like */
+        default:
+          res = FALSE;
+      }
+      break;
+    case GST_FORMAT_TIME:
+      switch (*dest_format) {
+        case GST_FORMAT_BYTES:
+          scale = 3 * (dec->info.pic_width * dec->info.pic_height) / 2;
+        case GST_FORMAT_DEFAULT:
+          if (dec->info.fps_numerator && dec->info.fps_denominator)
+            *dest_value = scale * gst_util_uint64_scale (src_value,
+                dec->info.fps_numerator,
+                dec->info.fps_denominator * GST_SECOND);
+          else
+            res = FALSE;
+          break;
+        default:
+          res = FALSE;
+      }
+      break;
+    case GST_FORMAT_DEFAULT:
+      switch (*dest_format) {
+        case GST_FORMAT_TIME:
+          if (dec->info.fps_numerator && dec->info.fps_denominator)
+            *dest_value = gst_util_uint64_scale (src_value,
+                GST_SECOND * dec->info.fps_denominator,
+                dec->info.fps_numerator);
+          else
+            res = FALSE;
+          break;
+        case GST_FORMAT_BYTES:
+          *dest_value = gst_util_uint64_scale_int (src_value,
+              3 * dec->info.pic_width * dec->info.pic_height, 2);
+          break;
+        default:
+          res = FALSE;
+      }
+      break;
+    default:
+      res = FALSE;
+  }
+done:
+  gst_object_unref (dec);
+  return res;
+
+  /* ERRORS */
+no_header:
+  {
+    GST_DEBUG_OBJECT (dec, "no header yet, cannot convert");
+    res = FALSE;
+    goto done;
+  }
+}
+
+static gboolean
+theora_dec_sink_convert (GstPad * pad,
+    GstFormat src_format, gint64 src_value,
+    GstFormat * dest_format, gint64 * dest_value)
+{
+  gboolean res = TRUE;
+  GstTheoraExpDec *dec;
+
+  if (src_format == *dest_format) {
+    *dest_value = src_value;
+    return TRUE;
+  }
+
+  dec = GST_THEORA_DEC (gst_pad_get_parent (pad));
+
+  /* we need the info part before we can done something */
+  if (!dec->have_header)
+    goto no_header;
+
+  switch (src_format) {
+    case GST_FORMAT_DEFAULT:
+      switch (*dest_format) {
+        case GST_FORMAT_TIME:
+          *dest_value = gst_theoradec_granule_clocktime (dec, src_value);
+          break;
+        default:
+          res = FALSE;
+      }
+      break;
+    case GST_FORMAT_TIME:
+      switch (*dest_format) {
+        case GST_FORMAT_DEFAULT:
+        {
+          guint rest;
+
+          if (!dec->info.fps_numerator || !dec->info.fps_denominator) {
+            res = FALSE;
+            break;
+          }
+
+          /* framecount */
+          *dest_value = gst_util_uint64_scale (src_value,
+              dec->info.fps_numerator, GST_SECOND * dec->info.fps_denominator);
+
+          /* funny way of calculating granulepos in theora */
+          rest = *dest_value / (1 << dec->info.keyframe_granule_shift);
+          *dest_value -= rest;
+          *dest_value <<= dec->info.keyframe_granule_shift;
+          *dest_value += rest;
+          break;
+        }
+        default:
+          res = FALSE;
+          break;
+      }
+      break;
+    default:
+      res = FALSE;
+  }
+done:
+  gst_object_unref (dec);
+  return res;
+
+  /* ERRORS */
+no_header:
+  {
+    GST_DEBUG_OBJECT (dec, "no header yet, cannot convert");
+    res = FALSE;
+    goto done;
+  }
+}
+
+static gboolean
+theora_dec_src_query (GstPad * pad, GstQuery * query)
+{
+  GstTheoraExpDec *dec;
+
+  gboolean res = FALSE;
+
+  dec = GST_THEORA_DEC (gst_pad_get_parent (pad));
+
+  switch (GST_QUERY_TYPE (query)) {
+    case GST_QUERY_POSITION:
+    {
+      gint64 granulepos, value;
+      GstFormat my_format, format;
+      gint64 time;
+
+      /* we can convert a granule position to everything */
+      granulepos = dec->granulepos;
+
+      GST_LOG_OBJECT (dec,
+          "query %p: we have current granule: %lld", query, granulepos);
+
+      /* parse format */
+      gst_query_parse_position (query, &format, NULL);
+
+      /* and convert to the final format in two steps with time as the 
+       * intermediate step */
+      my_format = GST_FORMAT_TIME;
+      if (!(res =
+              theora_dec_sink_convert (dec->sinkpad, GST_FORMAT_DEFAULT,
+                  granulepos, &my_format, &time)))
+        goto error;
+
+      time = (time - dec->segment.start) + dec->segment.time;
+
+      GST_LOG_OBJECT (dec,
+          "query %p: our time: %" GST_TIME_FORMAT, query, GST_TIME_ARGS (time));
+
+      if (!(res =
+              theora_dec_src_convert (pad, my_format, time, &format, &value)))
+        goto error;
+
+      gst_query_set_position (query, format, value);
+
+      GST_LOG_OBJECT (dec,
+          "query %p: we return %lld (format %u)", query, value, format);
+
+      break;
+    }
+    case GST_QUERY_DURATION:
+      /* forward to peer for total */
+      if (!(res = gst_pad_query (GST_PAD_PEER (dec->sinkpad), query)))
+        goto error;
+      break;
+    case GST_QUERY_CONVERT:
+    {
+      GstFormat src_fmt, dest_fmt;
+      gint64 src_val, dest_val;
+
+      gst_query_parse_convert (query, &src_fmt, &src_val, &dest_fmt, &dest_val);
+      if (!(res =
+              theora_dec_src_convert (pad, src_fmt, src_val, &dest_fmt,
+                  &dest_val)))
+        goto error;
+
+      gst_query_set_convert (query, src_fmt, src_val, dest_fmt, dest_val);
+      break;
+    }
+    default:
+      res = gst_pad_query_default (pad, query);
+      break;
+  }
+done:
+  gst_object_unref (dec);
+
+  return res;
+
+  /* ERRORS */
+error:
+  {
+    GST_DEBUG_OBJECT (dec, "query failed");
+    goto done;
+  }
+}
+
+static gboolean
+theora_dec_sink_query (GstPad * pad, GstQuery * query)
+{
+  gboolean res = FALSE;
+
+  switch (GST_QUERY_TYPE (query)) {
+    case GST_QUERY_CONVERT:
+    {
+      GstFormat src_fmt, dest_fmt;
+      gint64 src_val, dest_val;
+
+      gst_query_parse_convert (query, &src_fmt, &src_val, &dest_fmt, &dest_val);
+      if (!(res =
+              theora_dec_sink_convert (pad, src_fmt, src_val, &dest_fmt,
+                  &dest_val)))
+        goto error;
+
+      gst_query_set_convert (query, src_fmt, src_val, dest_fmt, dest_val);
+      break;
+    }
+    default:
+      res = gst_pad_query_default (pad, query);
+      break;
+  }
+
+error:
+  return res;
+}
+
+static gboolean
+theora_dec_src_event (GstPad * pad, GstEvent * event)
+{
+  gboolean res = TRUE;
+  GstTheoraExpDec *dec;
+
+  dec = GST_THEORA_DEC (gst_pad_get_parent (pad));
+
+  switch (GST_EVENT_TYPE (event)) {
+    case GST_EVENT_SEEK:
+    {
+      GstFormat format, tformat;
+      gdouble rate;
+      GstEvent *real_seek;
+      GstSeekFlags flags;
+      GstSeekType cur_type, stop_type;
+      gint64 cur, stop;
+      gint64 tcur, tstop;
+
+      gst_event_parse_seek (event, &rate, &format, &flags, &cur_type, &cur,
+          &stop_type, &stop);
+
+      /* we have to ask our peer to seek to time here as we know
+       * nothing about how to generate a granulepos from the src
+       * formats or anything.
+       * 
+       * First bring the requested format to time 
+       */
+      tformat = GST_FORMAT_TIME;
+      if (!(res = theora_dec_src_convert (pad, format, cur, &tformat, &tcur)))
+        goto convert_error;
+      if (!(res = theora_dec_src_convert (pad, format, stop, &tformat, &tstop)))
+        goto convert_error;
+
+      /* then seek with time on the peer */
+      real_seek = gst_event_new_seek (rate, GST_FORMAT_TIME,
+          flags, cur_type, tcur, stop_type, tstop);
+
+      res = gst_pad_push_event (dec->sinkpad, real_seek);
+
+      gst_event_unref (event);
+      break;
+    }
+    case GST_EVENT_QOS:
+    {
+      gdouble proportion;
+      GstClockTimeDiff diff;
+      GstClockTime timestamp;
+
+      gst_event_parse_qos (event, &proportion, &diff, &timestamp);
+
+      /* we cannot randomly skip frame decoding since we don't have
+       * B frames. we can however use the timestamp and diff to not
+       * push late frames. */
+      GST_OBJECT_LOCK (dec);
+      dec->proportion = proportion;
+      dec->earliest_time = timestamp + diff;
+      GST_OBJECT_UNLOCK (dec);
+
+      res = gst_pad_event_default (pad, event);
+      break;
+    }
+    default:
+      res = gst_pad_event_default (pad, event);
+      break;
+  }
+done:
+  gst_object_unref (dec);
+
+  return res;
+
+  /* ERRORS */
+convert_error:
+  {
+    GST_DEBUG_OBJECT (dec, "could not convert format");
+    gst_event_unref (event);
+    goto done;
+  }
+}
+
+static gboolean
+theora_dec_sink_event (GstPad * pad, GstEvent * event)
+{
+  gboolean ret = FALSE;
+  GstTheoraExpDec *dec;
+
+  dec = GST_THEORA_DEC (gst_pad_get_parent (pad));
+
+  GST_LOG_OBJECT (dec, "handling event");
+  switch (GST_EVENT_TYPE (event)) {
+    case GST_EVENT_FLUSH_START:
+      ret = gst_pad_push_event (dec->srcpad, event);
+      break;
+    case GST_EVENT_FLUSH_STOP:
+      /* TODO: Call appropriate func with OC_DECCTL_SET_GRANPOS? */
+      gst_theoradec_reset (dec);
+      ret = gst_pad_push_event (dec->srcpad, event);
+      break;
+    case GST_EVENT_EOS:
+      ret = gst_pad_push_event (dec->srcpad, event);
+      break;
+    case GST_EVENT_NEWSEGMENT:
+    {
+      gboolean update;
+      GstFormat format;
+      gdouble rate;
+      gint64 start, stop, time;
+
+      gst_event_parse_new_segment (event, &update, &rate, &format, &start,
+          &stop, &time);
+
+      /* we need TIME and a positive rate */
+      if (format != GST_FORMAT_TIME)
+        goto newseg_wrong_format;
+
+      if (rate <= 0.0)
+        goto newseg_wrong_rate;
+
+      /* now configure the values */
+      gst_segment_set_newsegment (&dec->segment, update,
+          rate, format, start, stop, time);
+
+      /* and forward */
+      ret = gst_pad_push_event (dec->srcpad, event);
+      break;
+    }
+    default:
+      ret = gst_pad_push_event (dec->srcpad, event);
+      break;
+  }
+done:
+  gst_object_unref (dec);
+
+  return ret;
+
+  /* ERRORS */
+newseg_wrong_format:
+  {
+    GST_DEBUG_OBJECT (dec, "received non TIME newsegment");
+    goto done;
+  }
+newseg_wrong_rate:
+  {
+    GST_DEBUG_OBJECT (dec, "negative rates not supported yet");
+    goto done;
+  }
+}
+
+#define ROUND_UP_2(x) (((x) + 1) & ~1)
+#define ROUND_UP_4(x) (((x) + 3) & ~3)
+#define ROUND_UP_8(x) (((x) + 7) & ~7)
+
+static GstFlowReturn
+theora_handle_comment_packet (GstTheoraExpDec * dec, ogg_packet * packet)
+{
+  gchar *encoder = NULL;
+  GstBuffer *buf;
+  GstTagList *list;
+
+  GST_DEBUG_OBJECT (dec, "parsing comment packet");
+
+  buf = gst_buffer_new_and_alloc (packet->bytes);
+  memcpy (GST_BUFFER_DATA (buf), packet->packet, packet->bytes);
+
+  list =
+      gst_tag_list_from_vorbiscomment_buffer (buf, (guint8 *) "\201theora", 7,
+      &encoder);
+
+  gst_buffer_unref (buf);
+
+  if (!list) {
+    GST_ERROR_OBJECT (dec, "couldn't decode comments");
+    list = gst_tag_list_new ();
+  }
+  if (encoder) {
+    gst_tag_list_add (list, GST_TAG_MERGE_REPLACE,
+        GST_TAG_ENCODER, encoder, NULL);
+    g_free (encoder);
+  }
+  gst_tag_list_add (list, GST_TAG_MERGE_REPLACE,
+      GST_TAG_ENCODER_VERSION, dec->info.version_major,
+      GST_TAG_VIDEO_CODEC, "Theora", NULL);
+
+  if (dec->info.target_bitrate > 0) {
+    gst_tag_list_add (list, GST_TAG_MERGE_REPLACE,
+        GST_TAG_BITRATE, dec->info.target_bitrate,
+        GST_TAG_NOMINAL_BITRATE, dec->info.target_bitrate, NULL);
+  }
+
+  gst_element_found_tags_for_pad (GST_ELEMENT (dec), dec->srcpad, list);
+
+  return GST_FLOW_OK;
+}
+
+static GstFlowReturn
+theora_handle_type_packet (GstTheoraExpDec * dec, ogg_packet * packet)
+{
+  GstCaps *caps;
+  gint par_num, par_den;
+
+  GST_DEBUG_OBJECT (dec, "fps %d/%d, PAR %d/%d",
+      dec->info.fps_numerator, dec->info.fps_denominator,
+      dec->info.aspect_numerator, dec->info.aspect_denominator);
+
+  /* calculate par
+   * the info.aspect_* values reflect PAR;
+   * 0 for either is undefined; we're told to assume 1:1 */
+  par_num = dec->info.aspect_numerator;
+  par_den = dec->info.aspect_denominator;
+  if (par_num == 0 || par_den == 0) {
+    par_num = par_den = 1;
+  }
+  /* theora has:
+   *
+   *  frame_width/frame_height : dimension of the encoded frame 
+   *  pic_width/pic_height : dimension of the visible part
+   *  pic_x/pic_y : offset in encoded frame where visible part starts
+   */
+  GST_DEBUG_OBJECT (dec, "dimension %dx%d, PAR %d/%d", dec->info.frame_width,
+      dec->info.frame_height, par_num, par_den);
+  GST_DEBUG_OBJECT (dec, "pic dimension %dx%d, offset %d:%d",
+      dec->info.pic_width, dec->info.pic_height,
+      dec->info.pic_x, dec->info.pic_y);
+
+  /* add black borders to make width/height/offsets even. we need this because
+   * we cannot express an offset to the peer plugin. */
+  dec->width = ROUND_UP_2 (dec->info.pic_width + (dec->info.pic_x & 1));
+  dec->height = ROUND_UP_2 (dec->info.pic_height + (dec->info.pic_y & 1));
+  dec->offset_x = dec->info.pic_x & ~1;
+  dec->offset_y = dec->info.pic_y & ~1;
+
+  GST_DEBUG_OBJECT (dec, "after fixup frame dimension %dx%d, offset %d:%d",
+      dec->width, dec->height, dec->offset_x, dec->offset_y);
+
+  dec->dec = th_decode_alloc (&dec->info, dec->setup);
+
+  th_setup_free (dec->setup);
+  dec->setup = NULL;
+
+  caps = gst_caps_new_simple ("video/x-raw-yuv",
+      "format", GST_TYPE_FOURCC, GST_MAKE_FOURCC ('I', '4', '2', '0'),
+      "framerate", GST_TYPE_FRACTION,
+      dec->info.fps_numerator, dec->info.fps_denominator,
+      "pixel-aspect-ratio", GST_TYPE_FRACTION, par_num, par_den,
+      "width", G_TYPE_INT, dec->width, "height", G_TYPE_INT, dec->height, NULL);
+  gst_pad_set_caps (dec->srcpad, caps);
+  gst_caps_unref (caps);
+
+  dec->have_header = TRUE;
+
+  return GST_FLOW_OK;
+}
+
+static GstFlowReturn
+theora_handle_header_packet (GstTheoraExpDec * dec, ogg_packet * packet)
+{
+  GstFlowReturn res;
+  int ret;
+
+  GST_DEBUG_OBJECT (dec, "parsing header packet");
+
+  ret = th_decode_headerin (&dec->info, &dec->comment, &dec->setup, packet);
+  if (ret < 0)
+    goto header_read_error;
+
+  switch (packet->packet[0]) {
+    case 0x81:
+      res = theora_handle_comment_packet (dec, packet);
+      break;
+    case 0x82:
+      res = theora_handle_type_packet (dec, packet);
+      break;
+    default:
+      /* ignore */
+      g_warning ("unknown theora header packet found");
+    case 0x80:
+      /* nothing special, this is the identification header */
+      res = GST_FLOW_OK;
+      break;
+  }
+  return res;
+
+  /* ERRORS */
+header_read_error:
+  {
+    GST_WARNING_OBJECT (dec, "Header parsing failed: %d", ret);
+    GST_ELEMENT_ERROR (GST_ELEMENT (dec), STREAM, DECODE,
+        (NULL), ("couldn't read header packet"));
+    return GST_FLOW_ERROR;
+  }
+}
+
+/* FIXME, this needs to be moved to the demuxer */
+static GstFlowReturn
+theora_dec_push (GstTheoraExpDec * dec, GstBuffer * buf)
+{
+  GstFlowReturn result;
+  GstClockTime outtime = GST_BUFFER_TIMESTAMP (buf);
+
+  if (outtime == GST_CLOCK_TIME_NONE) {
+    dec->queued = g_list_append (dec->queued, buf);
+    GST_DEBUG_OBJECT (dec, "queued buffer");
+    result = GST_FLOW_OK;
+  } else {
+    if (dec->queued) {
+      gint64 size;
+      GList *walk;
+
+      GST_DEBUG_OBJECT (dec, "first buffer with time %" GST_TIME_FORMAT,
+          GST_TIME_ARGS (outtime));
+
+      size = g_list_length (dec->queued);
+      for (walk = dec->queued; walk; walk = g_list_next (walk)) {
+        GstBuffer *buffer = GST_BUFFER (walk->data);
+        GstClockTime time;
+
+        time = outtime - gst_util_uint64_scale_int (size * GST_SECOND,
+            dec->info.fps_denominator, dec->info.fps_numerator);
+
+        GST_DEBUG_OBJECT (dec, "patch buffer %lld %lld", size, time);
+        GST_BUFFER_TIMESTAMP (buffer) = time;
+        /* ignore the result.. */
+        gst_pad_push (dec->srcpad, buffer);
+        size--;
+      }
+      g_list_free (dec->queued);
+      dec->queued = NULL;
+    }
+    result = gst_pad_push (dec->srcpad, buf);
+  }
+
+  return result;
+}
+
+static GstFlowReturn
+theora_handle_data_packet (GstTheoraExpDec * dec, ogg_packet * packet,
+    GstClockTime outtime)
+{
+  /* normal data packet */
+  th_ycbcr_buffer yuv;
+  GstBuffer *out;
+  guint i;
+  gint out_size;
+  gint stride_y, stride_uv;
+  gint width, height;
+  gint cwidth, cheight;
+  GstFlowReturn result;
+  ogg_int64_t gp;
+
+  if (!dec->have_header)
+    goto not_initialized;
+
+  if (th_packet_iskeyframe (packet)) {
+    dec->need_keyframe = FALSE;
+  } else if (dec->need_keyframe) {
+    goto dropping;
+  }
+
+  /* this does the decoding */
+  if (th_decode_packetin (dec->dec, packet, &gp))
+    goto decode_error;
+
+  if (outtime != -1) {
+    gboolean need_skip;
+
+    GST_OBJECT_LOCK (dec);
+    /* check for QoS, don't perform the last steps of getting and
+     * pushing the buffers that are known to be late. */
+    /* FIXME, we can also entirely skip decoding if the next valid buffer is 
+     * known to be after a keyframe (using the granule_shift) */
+    need_skip = dec->earliest_time != -1 && outtime <= dec->earliest_time;
+    GST_OBJECT_UNLOCK (dec);
+
+    if (need_skip)
+      goto dropping_qos;
+  }
+
+  /* this does postprocessing and set up the decoded frame
+   * pointers in our yuv variable */
+  if (th_decode_ycbcr_out (dec->dec, yuv) < 0)
+    goto no_yuv;
+
+  if ((yuv[0].width != dec->info.frame_width) ||
+      (yuv[0].height != dec->info.frame_height))
+    goto wrong_dimensions;
+
+  width = dec->width;
+  height = dec->height;
+  cwidth = width / 2;
+  cheight = height / 2;
+
+  /* should get the stride from the caps, for now we round up to the nearest
+   * multiple of 4 because some element needs it. chroma needs special 
+   * treatment, see videotestsrc. */
+  stride_y = ROUND_UP_4 (width);
+  stride_uv = ROUND_UP_8 (width) / 2;
+
+  out_size = stride_y * height + stride_uv * cheight * 2;
+
+  /* now copy over the area contained in offset_x,offset_y,
+   * frame_width, frame_height */
+  result =
+      gst_pad_alloc_buffer_and_set_caps (dec->srcpad, GST_BUFFER_OFFSET_NONE,
+      out_size, GST_PAD_CAPS (dec->srcpad), &out);
+  if (result != GST_FLOW_OK)
+    goto no_buffer;
+
+  /* copy the visible region to the destination. This is actually pretty
+   * complicated and gstreamer doesn't support all the needed caps to do this
+   * correctly. For example, when we have an odd offset, we should only combine
+   * 1 row/column of luma samples with one chroma sample in colorspace conversion. 
+   * We compensate for this by adding a black border around the image when the
+   * offset or size is odd (see above).
+   */
+  {
+    guchar *dest_y, *src_y;
+    guchar *dest_u, *src_u;
+    guchar *dest_v, *src_v;
+    guint offset_u, offset_v;
+
+    dest_y = GST_BUFFER_DATA (out);
+    dest_u = dest_y + stride_y * height;
+    dest_v = dest_u + stride_uv * cheight;
+
+    src_y = yuv[0].data + dec->offset_x + dec->offset_y * yuv[0].ystride;
+
+    for (i = 0; i < height; i++) {
+      memcpy (dest_y, src_y, width);
+
+      dest_y += stride_y;
+      src_y += yuv[0].ystride;
+    }
+
+    offset_u = dec->offset_x / 2 + dec->offset_y / 2 * yuv[1].ystride;
+    offset_v = dec->offset_x / 2 + dec->offset_y / 2 * yuv[2].ystride;
+
+    src_u = yuv[1].data + offset_u;
+    src_v = yuv[2].data + offset_v;
+
+    for (i = 0; i < cheight; i++) {
+      /* TODO: This, like many other things, is broken for pixel formats other
+       * than OC_PF_420
+       */
+      memcpy (dest_u, src_u, cwidth);
+      memcpy (dest_v, src_v, cwidth);
+
+      dest_u += stride_uv;
+      src_u += yuv[1].ystride;
+      dest_v += stride_uv;
+      src_v += yuv[2].ystride;
+    }
+  }
+
+  /* FIXME, frame_nr not correct */
+  GST_BUFFER_OFFSET (out) = dec->frame_nr;
+  dec->frame_nr++;
+  GST_BUFFER_OFFSET_END (out) = dec->frame_nr;
+  GST_BUFFER_DURATION (out) =
+      gst_util_uint64_scale_int (GST_SECOND, dec->info.fps_denominator,
+      dec->info.fps_numerator);
+  GST_BUFFER_TIMESTAMP (out) = outtime;
+
+  result = theora_dec_push (dec, out);
+
+  return result;
+
+  /* ERRORS */
+not_initialized:
+  {
+    GST_ELEMENT_ERROR (GST_ELEMENT (dec), STREAM, DECODE,
+        (NULL), ("no header sent yet"));
+    return GST_FLOW_ERROR;
+  }
+dropping:
+  {
+    GST_WARNING_OBJECT (dec, "dropping frame because we need a keyframe");
+    return GST_FLOW_OK;
+  }
+dropping_qos:
+  {
+    dec->frame_nr++;
+    GST_WARNING_OBJECT (dec, "dropping frame because of QoS");
+    return GST_FLOW_OK;
+  }
+decode_error:
+  {
+    GST_ELEMENT_ERROR (GST_ELEMENT (dec), STREAM, DECODE,
+        (NULL), ("theora decoder did not decode data packet"));
+    return GST_FLOW_ERROR;
+  }
+no_yuv:
+  {
+    GST_ELEMENT_ERROR (GST_ELEMENT (dec), STREAM, DECODE,
+        (NULL), ("couldn't read out YUV image"));
+    return GST_FLOW_ERROR;
+  }
+wrong_dimensions:
+  {
+    GST_ELEMENT_ERROR (GST_ELEMENT (dec), STREAM, FORMAT,
+        (NULL), ("dimensions of image do not match header"));
+    return GST_FLOW_ERROR;
+  }
+no_buffer:
+  {
+    GST_DEBUG_OBJECT (dec, "could not get buffer, reason: %s",
+        gst_flow_get_name (result));
+    return result;
+  }
+}
+
+static GstFlowReturn
+theora_dec_chain (GstPad * pad, GstBuffer * buf)
+{
+  GstTheoraExpDec *dec;
+  ogg_packet packet;
+  GstFlowReturn result = GST_FLOW_OK;
+
+  dec = GST_THEORA_DEC (gst_pad_get_parent (pad));
+
+  /* resync on DISCONT */
+  if (G_UNLIKELY (GST_BUFFER_FLAG_IS_SET (buf, GST_BUFFER_FLAG_DISCONT))) {
+    dec->need_keyframe = TRUE;
+    dec->last_timestamp = -1;
+    dec->granulepos = -1;
+  }
+
+  GST_DEBUG ("Offset end is %d, k-g-s %d", (int) (GST_BUFFER_OFFSET_END (buf)),
+      dec->info.keyframe_granule_shift);
+  /* make ogg_packet out of the buffer */
+  packet.packet = GST_BUFFER_DATA (buf);
+  packet.bytes = GST_BUFFER_SIZE (buf);
+  packet.granulepos = GST_BUFFER_OFFSET_END (buf);
+  packet.packetno = 0;          /* we don't really care */
+  packet.b_o_s = dec->have_header ? 0 : 1;
+  /* EOS does not matter for the decoder */
+  packet.e_o_s = 0;
+
+  if (dec->have_header) {
+    if (packet.granulepos != -1) {
+      GST_DEBUG_OBJECT (dec, "Granulepos from packet: %lld", packet.granulepos);
+      dec->granulepos = packet.granulepos;
+      dec->last_timestamp =
+          gst_theoradec_granule_clocktime (dec, packet.granulepos);
+    } else if (dec->last_timestamp != -1) {
+      GST_DEBUG_OBJECT (dec, "Granulepos inferred?: %lld", dec->granulepos);
+      dec->last_timestamp =
+          gst_theoradec_granule_clocktime (dec, dec->granulepos);
+    } else {
+      GST_DEBUG_OBJECT (dec, "Granulepos unknown");
+      dec->last_timestamp = GST_CLOCK_TIME_NONE;
+    }
+  } else {
+    GST_DEBUG_OBJECT (dec, "Granulepos not usable: no headers seen");
+    dec->last_timestamp = -1;
+  }
+
+  GST_DEBUG_OBJECT (dec, "header=%d packetno=%lld, outtime=%" GST_TIME_FORMAT,
+      packet.packet[0], packet.packetno, GST_TIME_ARGS (dec->last_timestamp));
+
+  /* switch depending on packet type */
+  if (packet.packet[0] & 0x80) {
+    if (dec->have_header) {
+      GST_WARNING_OBJECT (GST_OBJECT (dec), "Ignoring header");
+      goto done;
+    }
+    result = theora_handle_header_packet (dec, &packet);
+  } else {
+    result = theora_handle_data_packet (dec, &packet, dec->last_timestamp);
+  }
+
+done:
+  /* interpolate granule pos */
+  dec->granulepos = inc_granulepos (dec, dec->granulepos);
+
+  gst_object_unref (dec);
+
+  gst_buffer_unref (buf);
+
+  return result;
+}
+
+static GstStateChangeReturn
+theora_dec_change_state (GstElement * element, GstStateChange transition)
+{
+  GstTheoraExpDec *dec = GST_THEORA_DEC (element);
+  GstStateChangeReturn ret;
+
+
+  switch (transition) {
+    case GST_STATE_CHANGE_NULL_TO_READY:
+      break;
+    case GST_STATE_CHANGE_READY_TO_PAUSED:
+      th_info_init (&dec->info);
+      th_comment_init (&dec->comment);
+      dec->have_header = FALSE;
+      gst_theoradec_reset (dec);
+      break;
+    case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
+      break;
+    default:
+      break;
+  }
+
+  ret = parent_class->change_state (element, transition);
+
+  switch (transition) {
+    case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
+      break;
+    case GST_STATE_CHANGE_PAUSED_TO_READY:
+      th_decode_free (dec->dec);
+      dec->dec = NULL;
+
+      th_comment_clear (&dec->comment);
+      th_info_clear (&dec->info);
+      break;
+    case GST_STATE_CHANGE_READY_TO_NULL:
+      break;
+    default:
+      break;
+  }
+
+  return ret;
+}
+
+static gboolean
+plugin_init (GstPlugin * plugin)
+{
+  if (!gst_element_register (plugin, "theoradecexp", GST_RANK_PRIMARY,
+          gst_theoradec_get_type ()))
+    return FALSE;
+
+  return TRUE;
+}
+
+GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
+    GST_VERSION_MINOR,
+    "theoradec",
+    "Theora dec (exp) plugin library",
+    plugin_init, VERSION, "LGPL", GST_PACKAGE, GST_ORIGIN)
diff --git a/ext/theora/theoradec.h b/ext/theora/theoradec.h
new file mode 100644
index 00000000..a19b04dd
--- /dev/null
+++ b/ext/theora/theoradec.h
@@ -0,0 +1,96 @@
+/* GStreamer
+ * Copyright (C) 2004 Benjamin Otte <in7y118@public.uni-hamburg.de>
+ *               2006 Michael Smith <msmith@fluendo.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifndef __GST_THEORADEC_H__
+#define __GST_THEORADEC_H__
+
+#ifdef HAVE_CONFIG_H
+#  include "config.h"
+#endif
+
+#include <gst/gst.h>
+#include <theora/theoradec.h>
+#include <string.h>
+
+G_BEGIN_DECLS
+
+#define GST_TYPE_THEORA_DEC \
+  (gst_theoradec_get_type())
+#define GST_THEORA_DEC(obj) \
+  (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_THEORA_DEC,GstTheoraExpDec))
+#define GST_THEORA_DEC_CLASS(klass) \
+  (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_THEORA_DEC,GstTheoraExpDec))
+#define GST_IS_THEORA_DEC(obj) \
+  (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_THEORA_DEC))
+#define GST_IS_THEORA_DEC_CLASS(obj) \
+  (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_THEORA_DEC))
+
+typedef struct _GstTheoraExpDec GstTheoraExpDec;
+typedef struct _GstTheoraExpDecClass GstTheoraExpDecClass;
+
+/**
+ * GstTheoraExpDec:
+ *
+ * Decoder using theora-exp
+ */
+struct _GstTheoraExpDec
+{
+  GstElement element;
+
+  /* Pads */
+  GstPad *sinkpad;
+  GstPad *srcpad;
+
+  /* theora decoder state */
+  th_dec_ctx *dec;
+  th_setup_info *setup;
+
+  theora_info info;
+  th_comment comment;
+
+  gboolean have_header;
+  guint64 granulepos;
+  guint64 granule_shift;
+
+  GstClockTime last_timestamp;
+  gboolean need_keyframe;
+  gint width, height;
+  gint offset_x, offset_y;
+
+  int frame_nr;
+
+  GList *queued;
+
+  /* segment info */ /* with STREAM_LOCK */
+  GstSegment segment;
+
+  /* QoS stuff */ /* with LOCK*/
+  gboolean proportion;
+  GstClockTime earliest_time;
+};
+
+struct _GstTheoraExpDecClass
+{
+  GstElementClass parent_class;
+};
+
+G_END_DECLS
+
+#endif /* __GST_THEORADEC_H__ */